与SSIS 2008表现得很厉害......

通常情况下，Microsoft在新版本的后向兼容性组件上努力，以便在旧版本中开发的任何内容继续运行。随着SQL Server支持越来越多的功能，这成为一个更加困难的任务。多年来我们已经看到了一些艰难的升级。SQL Server 6.5至7.0来介意。SQL Server 2000到2005也不容易。例如，SQL Server 2005中引入了SQL Server集成服务作为新版本的DTS 2000.然而，Microsoft让我们知道，由于SSIS是一个完整的重写，因此无法保证100％的DTS代码可以转换为SSIS模型。好的，SSIS提供了更大的可扩展性和功能，但向后兼容性对于投入无数小时开发的用户来说是一个大问题。该解决方案是继续与SSIS并联支持DTS包，以便封装迁移可以延迟到稍后的时间。可以从SSIS包中执行现有的DTS包，没有更改。 However, the reality was that most packages would need to be re-written in SSIS to benefit from the new architecture. Microsoft has now let us know that DTS will no longer be supported at the next major release which presumably will be within the next couple years so the clock is ticking. With SQL Server 2008 being an incremental release you would have thought that upgrading packages from SSIS 2005 would be fairly straight forward. Not so fast. One big difference I have noticed is the execution of packages using configuration files. These files allow you to modify variables at run-time giving a dynamic approach to your packages. At design time, you define the variables, provide default values and generate a configuration file. At deployment, that configuration file is used by the Package Installer Wizard. In SSIS 2005, we could use a copy of the configuration file at run-time with changes to the variable values to override the design-time values using the /ConfigFile switch of DTEXEC.exe. Now in SSIS 2008, this strategy will not work. This is because the design-time variable values are reloaded after any configuration changes. So, executing a package with the same DTEXEC command from 2005 will produce different results in 2008. Not good. At first I thought this must be my mistake. After thorough testing, I thought it was a bug. Then I found out that it was a feature. Don’t believe me? Check out “Behavior Changes to Integration Services Features in SQL Server 2008” at http://msdn.microsoft.com/en-us/library/bb500430.aspx and look for “Behavior Changes Related to Package Configurations”. It’s meant to work that way. So Microsoft can say “it works as designed”. If you are upgrading from SSIS 2005, I recommend studying that topic carefully and performing thorough testing. I am not entirely sure why this was changed, (ours is not to question why) but now in SSIS 2008 our strategy has to change. You can still provide a run-time configuration file but the variables referenced cannot be the same as in the design-time configuration file otherwise they will be reset to the default values. All this comes out in testing but it’s a shame that the behavior had to change with no option to maintain the 2005 behavior. I guess that would be too confusing. And this is not? As I always say, think of it as job security. If it was easy, everyone would be doing it. Cheers Brian